Method for making higher alcohols



Nov. 19, 1940;

H. s. SCHNEIDER 2,221,955

METHOD FOR MAKING HIGHER ALCOI-IbLS Filed June 6, 1936 i ii 16 j COLLECT/ON Var-SS5.

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Patented Nov. is, 1940 UNITED ,sTATEs.

lATENT oFFIca".

' 2,221,955 METHOD non MAKING manna snconoLs Hclmuth G. Schneider, Roselle, N. 1.,

V Standard Alcohol Company assignmto Application June a, 1936, Serial No. cases The present invention relates to an improved process for producing higher alcohols from olefins, and more specifically to a catalytic process for producing alcohols containing at least fourcarbon atoms. The invention will be fully un'- derstood from the following description and the drawing;

The drawing represents a diagrammatic view in sectional elevation of an apparatus adapted to carry out the process of the invention and indicates the flow of materials.

The. present invention is an improved method for producing higher alcohols from the corresponding oleflns. In general, the processes forproducing the alcohols from olefins have been knownfor some time. In the prior ,art processes most frequently employed,th e olefin is brought into contact with concentrated sulfuric acid, the concentration being sufiicient to effect sulfation of the olefins, and results in the production of an olefin ester of the acid.\ The second step in the process consists in diluting the mixture with a largequantity of waterso as to reduce the acid concentration below the sulfating strength '25 and this is followed by distillation of the alcohol from the acid. ,Acid may be used after reconcen tration to the sulfating strength. In the present process, the function of the acid or other catalyst is quite diflerent in that it acts as a true catalyst.

so Sulfuric acid may be used as the catalyst but other materials are'also useful. In the case where sulfuric'acidis used, it is employed in a diluted state well below the sulfating strengthand preferably considerably lower. There is no 35 necessity for further dilution and the acid is recovered in substantially the same concentration .in which it was originally employed.

Referring to the drawing, pipe I represents the feed line by which the olefin or olefin mixture 40 is introduced into the process. The. olefin may ture is raised to a point suitable for the reaction. and the mixture is then discharged into I the lower end of a contact chamber 4. This chamber may be in the form of a tower fitted with indicated before.

.2 Claims. (01.260441) plates 5 and thus adapted to maintain a pool of liquid on each plate. The plates are fitted with bubbling caps 6which provide for a passage of a fluid from the lower to the next higher plate, but they are not provided with overflow tubes ordinarily used in distillation towers, so

that there is no means'b'y which the liquid may fiowv downwardly through the tower. Water may be introduced on to each of the plates by means of the pipe I. A suitable means, not shown, which may comprise a jacket, heating coils or the like, may be provided to maintain the reaction vessel at thepreferred temperature which will be disclosed below, and the reaction product after forcing its way upwardly through this reaction tower passes out through a pipe 8 and into a drum 9- fromwhich gaseous materials may be separated by a pipe It. The liquidproduct consisting of alcohol and alcohol-oil mixture flows from the trap by means of a line I I through a heating coil l2 andthence to an 'ordinary distillation tower l3. This may be fitted with the ordinary forms of rectifying plates which provide bubbling caps and overflow caps. as shown. Steam may be added at the base of the tower for heat by pipe I4 and a condensing coil 15 is provided at the top of the'tower to provide reflux for,distillation.v The distillate flows overhead by a vapor pipe l5 through a condenser l6 and into a collection vessel ll. The unreacted oil flows from the base of the tower by a pipe ll through a pump 19 and may be circulated through the heating coil 3' and the tower 4 as In the operation of the present process, it should be understood that the process is adapted particularly for the production of higher alcohol from oleflns containing four carbon atoms or more. The'cataly'st may comprise sulfuric acid diluted below thesulfating' strength. 30-65% sulfuric acid may be used, but it is preferableto employ a more diluted acid, for

example, 10 or 20% or even 5%, if desired. a

While sulfuric acid. is the best catalyst for all around operation, other materials maybe used as well, for example, phosphoric acid or hydrochloric acid, preferably also in dflutedconcentrationa. Diluted metal halide solutions may also be employed, such as cadmium, zinc, ammonium and aluminum halides. As a general rule, the more strongly acid the reaction and the material used in the catlyst, the lower is its most effective concentration in therpresent process.

For example, phosphoric acid seems to be most eflective at a concentration of about 15%. By-

drochloric acid at a strength 01.2% more eiiective than acetic acid at and aluminum chloride in aqueous solution at about is at about the best strength while zinc chloride is best at about 15%. In the further discussion of the process, the catalyst will be referred to as suli'uric acid because this is the preferred process, although it will be understoodthat the other catalysts may be used in its stead.

In operating the process, the sulfuric acid or other catalyst is maintained in the reaction vessel at the preferred concentration and from the previous description it will be seen that the aqueous catalyst is held in a series of zones through which the oil and .olefin mixture passes. There is a slight concentration of the catalyst due to the reaction and water must be added from time to time to maintain the proper dilute concentration of the acid. The olefin used may be in vapor phase, if desired, or it may be in liquid phase, but in either case provision is made for the mixture of vapor and liquid to pass; upwardly through the tower, passing through the pool of the acid catalyst to each plate in the reaction chamber. The tower is maintained at a temperature below 300 C. and preferably above about C. The upper limit to desirable to prevent side reactions and below the lower limit, the reaction rate is too small to be practically important. The preferred reaction temperature, however, is in the range from about C. to 150 C. If lower ole.- fins are used, such as butylenes, it is preferable to operate at an elevated pressure and to maintain them in a liquid state. I a

Pure olefins may be used such as butylene or amylene or mixtures of 'the type obtained by the cracking of hydrocarbon oils. A sumcient volume of saturated hydrocarbons should be present so as to effectively dissolve all of the alcohol 40 from the acid solutions This oil may be of the type of naphtha, kerosene or gas oil and preferably can be cut at such a boiling range that'it may be readily separated from the alcohol produced. In the drawing accompanying the present application, it is assumed that an oil having as to remove the alcohol by distillation from the oil. On the other hand, it will be understood that a lighter oil may be employed; for example, a light naphtha might be used and in this case the naphtha would be removed from the alcohol by distillation, and the alcohol would be recovered at the base of the towerji 3.

Example 1' 22 liters of C4 hydrocarbons containing 11 isobutylene were passed through a lead lined absorption tower at the rate 019.5 liters per hour all novelty inherent in the :for the said alcohol than for the other constituasanocs using 4 liters of 49% H2804 at 35 C. and 40 lbs.- per sq. in. pressure. p Total isobutylene in feed=1452 grams isobutylene absorbed by acid=850 grams Tertiary butyl alcohol recovered from spent naphtha (by distillation) -'367 cc.= 217 grams isobutylene Total isobutylene extracted=1067 grams='l3.l5%'

Per cent isobutylene absorbed, extracted as alcohol with spent naphtha=20.4%

Example 2 Feed rate 04 cut" 81 liters per hour using 4 liters 49% H2804 at 45 C. and lbs. per sq. 1D,:

pressure. 7 g 15 Total isobutylene in feed=2940 grams isobutylene absorbed in acid=1300 grams iertiary butyl alcohol in spent naphtha=87-5 .cc.,

equivalent to 515 grams isobutylene 20 Total isobutylene reacted=62% 1 Per cent isobutylene absorbed, extracted as alcohol in spent naphtha- 28.4%

t The present process is\not to be limited by any theory of the operation of the process; nor to the hydration of any particular olefin, nor to the use of any particular catalyst, but only to'the following claims in which it is desired to claim invention. I claim: i 1. A continuous process for converting an olefin into a corresponding alcohol which comprises continuously passing an olefin having at least 4 carbon atoms into a reaction zone containing ,v water and acatalyst capable of converting said 35 olefin to a corresponding alcohol, maintaining said reaction zone under conversion conditions, concurrently introducing into said reactionzone a solvent having a relatively higher solvent power ents in said. reaction 'zonefcorltinuously withdrawing from the reaction zone the solvent containing alcohol dissolved therein and separating alcohol therefrom.

2; A process for converting anolefln having 4 carbon atoms to the molecule to a corresponding alcohol which comprises passing said olefin into a reaction zone containing sulfuric acid of 30 to 65% concentration, maintaining said reaction zone under, conversion conditions, concurrently introducing in said reaction zone water suilicient to compensate for the water used up in the reaction to form the alcohol and asolvent having a relatively higher solvent power for said alcohol than for other constituents in said reaction zone,

. continuously withdrawing the'solvent containing 

